[Mesa-dev] [RFC] OES_external_image for i965

[Pohjolainen, Topi]

On Fri, Mar 01, 2013 at 10:03:45AM -0500, Kristian H?gsberg wrote:
> On Fri, Mar 1, 2013 at 3:51 AM, Pohjolainen, Topi
> <topi.pohjolainen at intel.com> wrote:
> > On Tue, Feb 26, 2013 at 04:05:25PM +0000, Tom Cooksey wrote:
> >> Hi Topi,
> >>
> >> > The second more or less questionable part is the support for creating YUV
> >> > buffers. In order to test for YUV sampling one needs a way of providing them
> >> > for the EGL stack. Here I chose to augment the dri driver backing gbm as I
> >> > couldn't come up with anything better. It may be helpful to take a look at the
> >> > corresponding piglit test case and framework support I've written for it.
> >>
> >> You might want to take a look at the EGL_EXT_image_dma_buf_import[i] which has been written
> >> specifically for this purpose. Though this does assume you have a driver which supports exporting a
> >> YUV buffer it has allocated with dma_buf, such as a v4l2 driver or even ion on Android.
> >>
> >
> > It certainly looks good addressing not only the individual plane setup but
> > allowing one to control also the conversion coefficients and subsampling
> > position.
> > Coming from piglit testing point of view, do you have any ideas where to
> > allocate the buffers from? I guess people wouldn't be too happy seeing v4l2 tied
> > into piglit, for example.
> 
> SInce you're already using intel specific ioctls to mmap the buffers,
> I'd suggest you just go all the way and allocate using intel specific
> ioctls (like my simple-yuv.c example).  I don't really see any other
> approach, but it's not pretty...
> 

I used gbm buffer objects in order to match the logic later in
'dri2_drm_create_image_khr()' which expects the buffer to be of the type
'gbm_dri_bo' (gbm_bo) for the target EGL_NATIVE_PIXMAP_KHR. Giving drm buffer
objects instead would require new target, I guess?

Topi